Random thought I had, while doing my research/studies.

Not all, but most, beneficial insects to the garden are thusly so because they are carnivores.

Just thought that was funny and ironic

The uneasy symbiosis of vegetarians and meat eaters has been going on in the human world for millennia also. In India, Hindus mostly consider their cattle sacred, and will by no means eat them. But they are important parts in the food system nevertheless, being used for plowing and hauling wagons, milking, and manure (which finds uses as a plaster and as fuel, as well as fertilizer). But refusing to eat them quickly leads to a cow population problem, particularly of bull calves. So what the Hindus refuse to eat, the many millions of Muslims, Christians and others living in their midst are more than happy to take off their hands, and even now, with otherwise uneasy relations at times between the now partitioned countries of "greater India", large herds of cattle are driven across the borders into Pakistan and Bangladesh at Eid, one of the big Muslim holidays when a big feast featuring beef is the tradition.

Whether they are predator or beneficial depends on whether they eat what we eat, or they eat the other thing that eats what we eat. The enemy of my enemy is my friend...